GPS/NAV Computer System Failures
#1 GPS/NAV Failure
1. BOTH ON GPS 2 ...................................... VERIFY ANNUNCIATED ON PFD
2. TAWS FAIL
............................................... VERIFY ANNUNCIATED ON PFD
3. In-Flight Corrective Action.........................MAINTAIN VISUAL SEPARATION
FROM TERRAIN
#2 GPS/NAV Failure
1. BOTH ON GPS 1 .................................................... ANNUNCIATED ON PFD
2. In Flight Corrective Action
..................................................... NONE NEEDED
Dual GPS/NAV Failure
Annunciations Shown:
• NAV 1&2 – RED “X”
• COM 1&2 – RED “X”
• TAWS FAIL
• HSI/GPS INTEG
• XPDR FAIL
• NO GPS POSITION
• NO TRFC DATA
• ALL ENGINE GAUGES and EIS – RED “X”
• CLOCK – RED “X”
1. GPS/NAV Circuit Breakers
............................................................CHECK IN
2. If Open
................................................ RESET (close) CIRCUIT BREAKERS
3. If Circuit Breakers Open Again
............................................ DO NOT RESET
4. COM 1
............................................................USE to transmit on 121.5 MHz
(automatically defaults to this frequency)
5. If VFR
.................................................................Maintain VFR to destination
6. If IFR
.......................................REQUEST ATC for vectors to VFR conditions
NOTE: TAWS fails because it relies on the #1 GPS for position
information.
NOTE: Even though the COM 1 frequency box no longer displays a
frequency (red “X” shown), the radio will transmit on 121.5 MHz (Guard).